The broad objective of this study is the development of theoretical, conceptual, and experimental tools for dealing with the chemical separation of biological molecules. Our main focus presently is on field-flow fractionation (FFF) and its different sub-techniques. Experimental work is being done in an attempt to make FFF a viable separations tool for macromolecules, in accord with its theoretical potential. Work is also continuing on the high pressure gas chromatography of medium and high molecular weight substances.